Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.6 (RNA polymerase)
34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Wells' syndrome, or eosinophilic cellulitis, is a rare dermatosis characterized histologically by a dermal infiltrate of eosinophils, lymphocytes and histiocytes between collagen bundles and amorphous or granular eosinophilic deposits on collagen, constituting flame figures. We report a 54-year-old woman with eosinophilic cellulitis whose peripheral blood showed a marked eosinophilia and a high proportion of CD4+CD7- cells before treatment. Reverse transcriptase-polymerase chain reaction revealed that CD4+CD7- cells, but neither CD4+CD7+ nor CD4-CD8+ cells, in the circulating mononuclear cells expressed mRNA for interleukin (IL)-5, the major cytokine involved in eosinophilia. The proportion of CD4+CD7- cells decreased, and expression of mRNA for IL-5 disappeared in the peripheral blood, when the disease was treated by the administration of intravenous recombinant interferon-gamma. These findings suggest that circulating CD4+CD7- T cells play a pivotal role in the pathogenesis of eosinophilic cellulitis by producing IL-5.
Br J Dermatol 1997 Jun
PMID:Wells' syndrome: a pathogenic role for circulating CD4+CD7- T cells expressing interleukin-5 mRNA. 921 26

Although the TGF-beta family of growth factors probably regulates skin and hair follicle development, its exact role is still quite ill-defined. Here, we characterize the correlative expression pattern of the interdependent high affinity receptor proteins for TGF-beta1 and TGF-beta3, TGF-beta receptor type I (TGF-betaRI) and TGF-beta receptor type II (TGF-betaRII), during hair follicle development and cycling in C57BL/6 mice. During neonatal follicle development, TGF-betaRII immunoreactivity is confined to epithelial cells. Focal epidermal TGF-betaRII expression is seen even before actual hair placode formation. In contrast to the TGF-betaRII immunoreactivity in the outer root sheath, precortical hair matrix and inner root sheath cells were TGF-betaRII negative during hair bulb morphogenesis. TGF-betaRI (Alk-5) immunoreactivity largely overlapped the TGF-betaRII expression pattern, but was more widespread. During hair follicle cycling in adolescent mice, TGF-betaRII immunoreactivity was restricted to follicles, and was strikingly hair cycle dependent (maximal immunoreactivity: anagen VI and early catagen). Again, TGF-betaRI (Alk-5) immunoreactivity co-localized with TGF-betaRII immunoreactivity, but was more extensive. Reverse transcriptase polymerase chain reaction analysis of TGF-betaRII mRNA confirmed peak transcript levels in back skin with most hair follicles in the anagen VI-catagen transformation. mRNA levels of TGF-betaRI (Alk-5) did not vary significantly during the hair cycle, whereas those of TGF-betaRI (threonine-serine kinase 7 L) declined during early anagen, and were maximal during the anagen-catagen transition. This provides a basis for defining the choreography of TGF-beta-related signalling during hair follicle morphogenesis and cycling, introduces intraepidermal TGF-betaRII immunoreactivity as a marker for imminent follicle development, and supports the concept that both TGF-betaRII and TGF-betaRI stimulation is involved in, but not restricted to, the control of catagen induction.
J Invest Dermatol 1997 Oct
PMID:Transforming growth factor-beta receptor type I and type II expression during murine hair follicle development and cycling. 932 84

Reverse transcriptase polymerase chain reaction for the detection of tyrosinase-mRNA-positive cells in peripheral blood of melanoma patients, as a possible marker of hematogenous dissemination, has demonstrated varying detection rates. This study examined the sensitivity and reproducibility of the technique using a protocol of multiple polymerase chain reaction to determine circulating melanocytic cells. For each of the 123 melanoma patients included in this study, four nested polymerase chain reactions were performed from two blood specimens requiring both polymerase chain reactions from at least one blood sample to be positive to consider a patient as positive. Thus, a definitive result was obtained in 98% of the cases, whereas only 1.6% lacked conclusive findings. Thus, we found a correlation between the tyrosinase detection rate and the clinical stage. Circulating tyrosinase-mRNA-positive cells were detected in 13% of patients with primary tumor, 17% with regional skin/lymph node metastasis, and 44% with distant metastasis. Positivity also correlated with known melanoma progression markers such as gender, tumor thickness, and histologic type. Positive results were obtained more frequently in (i) men compared with women, (ii) patients with thick primary melanomas (> 4 mm: 38%) compared with those with thinner tumors (1.1-4 mm, 22%; < or = 1 mm, 5%), and (iii) patients with nonclassifiable (38%), nodular (34%), and occult primary melanomas (30%) compared with those with acrolentiginous (17%), superficial spreading (9%), or lentigo maligna melanoma (0%). These findings suggest that detection of tyrosinase-mRNA-positive cells in peripheral blood is not an adequate marker for identifying melanoma patients with distant metastasis. Reverse transcriptase polymerase chain positivity in early melanoma stages, however, as corresponding to other prognostic parameters, may indicate increased risk for the development of hematogenous metastasis and may be of value as a progression marker.
J Invest Dermatol 1998 Mar
PMID:RT-PCR for tyrosinase-mRNA-positive cells in peripheral blood: evaluation strategy and correlation with known prognostic markers in 123 melanoma patients. 950 46

Recent observations demonstrated that interleukin-1beta converting enzyme family proteases, now referred to as caspase family, play central roles in apoptosis, or programmed cell death. In this study, we tried to isolate and characterize epidermal caspases. By DEAE-Sephacel anion-exchange chromatography, human cornified cell extract showed two caspase-like fractions (F-I and F-II) with different substrate specificities. These were further purified by Sephacryl S-200, Mono Q ion exchange and Superose 6 gel chromatography. F-I showed a molecular weight of 30 kDa and specifically hydrolyzed acetyl-Asp-Glu-Val-Asp-methylcoumarinamide, a fluorogenic substrate for caspase-3 (CPP32) with a Km value of 13.8 microM. F-I generated a characteristic 85 kDa fragment from poly(ADP-ribose) polymerase. Inhibitor susceptibility of F-I was very similar to that of caspase-3, further confirming the caspase-3-like properties of F-I. In contrast, the molecular weight of F-II was estimated to be 110 kDa, which was much higher than the other caspases. F-II equally hydrolyzed acetyl-Asp-Glu-Val-Asp-methylcoumarinamide, and acetyl-Tyr-Val-Ala-Asp-methylcoumarinamide, caspase-1 (interleukin-1beta converting enzyme)-specific substrate, and was inhibited by acetyl-Tyr-Val-Ala-Asp-aldehyde and acetyl-Tyr-Val-Ala-Asp-aldehyde. Affinity labeling using biotinylated YVAD-cmk demonstrated several positive bands ranging from 25 to 35 kDa, supporting the hypothesis that F-II is a complex of multiple caspases. Reverse transcriptase-polymerase chain reaction analysis demonstrated that among known caspases tested, caspase-1, -2, -3, -4, and -7 were expressed in cultured human keratinocytes. These results suggest that multiple caspases are synthesized in human keratinocytes and are involved in terminal differentiation.
J Invest Dermatol 1998 Sep
PMID:Partial purification and characterization of two distinct types of caspases from human epidermis. 974 Feb 25

Epidermal cytokines such as interleukin (IL)-1beta, tumor necrosis factor-alpha, and IL-12 have been described to play a crucial role in the induction and elicitation phase of allergic contact dermatitis upon exposure to haptens. In this study we asked whether these cytokines may also play a role in the epidermis of patients with atopic dermatitis after the application of house dust mite antigens (HDM) to their skin. Epidermal samples were collected by scraping healthy appearing skin of atopic patients and healthy individuals 8 h after the application of an extract of HDM. Sodium lauryl sulfate and saline served as controls. Reverse transcriptase-polymerase chain reaction was performed for IL-1beta, tumor necrosis factor-alpha, IL-12 p35, and IL-12 p40. Exposure to HDM led to a significant upregulation of mRNA of these cytokines in atopic patients only. Whereas IL-1beta and tumor necrosis factor-alpha also showed an upregulation in part of these patients after exposure to the irritant sodium lauryl sulfate, IL-12 p40 mRNA was exclusively enhanced by the application of the allergen. In contrast to IL-12 p40, IL-12 p35 mRNA was not detectable in significant amounts. Interestingly, also in untreated, normal appearing skin of atopic individuals (n = 16), the levels of these cytokines were higher than in normal individuals (n = 8), possibly explaining the increased skin irritability of atopic individuals. Finally, comparing epidermal cytokines in the skin of patients who developed a positive allergen patch test to those who stayed negative, suggests that only expression of IL-1beta mRNA may be a predictive marker for the development of a positive patch test reaction to HDM.
J Invest Dermatol 1998 Dec
PMID:Epidermal cytokines IL-1beta, TNF-alpha, and IL-12 in patients with atopic dermatitis: response to application of house dust mite antigens. 985 37

High levels of 5alpha-reductase activity have been detected in human apocrine glands, and the concentration of dihydrotestosterone has been found to be higher than that of testosterone in the nuclear fraction of the skin of patients who suffer from excessive or abnormal odour derived from apocrine sweat (osmidrosis). Although these results suggest that 5alpha-reductase may play a central role in the action of androgens in the apocrine gland, the isozyme responsible is not known. We therefore assayed 5alpha-reductase type I and type II activity and mRNA expression in isolated apocrine glands from four patients with osmidrosis. When we incubated gland homogenates with [3H]testosterone, we found that the biochemical properties of the apocrine gland enzyme were consistent with those of type I 5alpha-reductase: at substrate concentrations of both 50 nmol/L and 1 micromol/L, the optimum pH was in the range 6.0-7.5, and the apparent Km was 21.1 micromol/L. The apocrine gland enzyme was inhibited by MK386, a specific inhibitor of type I 5alpha-reductase, in a dose-dependent manner, but it was hardly affected by finasteride, a specific inhibitor of type II isozyme, in that a nanomolar concentration of finasteride produced only a slight inhibition. Reverse transcriptase-polymerase chain reaction showed that the apocrine gland expressed type I 5alpha-reductase mRNA exclusively, except for a faint band of type II isozyme in a few preparations. These data indicate that the type I isozyme is the predominant form of 5alpha-reductase in the apocrine gland and may play a central role in the anabolic activity of androgens, as reported for the sebaceous gland. In addition, a small amount of type II isozyme may be expressed by mesenchymal cells that surround the apocrine glands and also contribute to their development.
Br J Dermatol 1998 Nov
PMID:Predominance of type I 5alpha-reductase in apocrine sweat glands of patients with excessive or abnormal odour derived from apocrine sweat (osmidrosis). 989 45

It has been recently hypothesized that superantigens play a precipitating or aggravating role in psoriasis. Aside from streptococcal infection, Staphylococcus aureus can be sometimes detected in the tonsils of patients with psoriasis arthropathy (PA), although its significance in the pathogenesis of PA is still unknown. These focal infections are thought to be a possible triggering factor of the arthralgia, as well as the cutaneous manifestations, in PA. In this study, we have investigated the response of peripheral blood mononuclear cells (PBMC) from patients with PA to staphylococcal superantigens and analyzed its association with clinical and laboratory findings. 3H-TdR uptake by PBMC was examined after 7 days' culture with concanavalin A (Con A), staphylococcal enterotoxin A (SEA), SEB and SEC1. Results showed that there was no significant difference in either the unstimulated or Con A-stimulated PBMC response between psoriasis vulgaris patients (PASI score < 10) (n = 15), PA patients (n = 11) and normal controls (n = 19). Among 11 PA patients, 8 patients responded most intensely to SEB, while 2 patients showed the strongest response to SEA, and another responded mainly to SEC1. The PBMC response against SEB in patients with PA (38,715 719 dpm, stimulation index (SI); 50.2 41.4) (mean SD) was significantly higher than that in normal controls (23,708 466 dpm, SI; 30.9 23.8) (p < 0.05), however, the difference between that of patients with PA and psoriasis vulgaris (33,428 467 dpm, SI; 42.8 30.6) did not reach significance. In addition, PBMC from psoriatic patients with a short episode of severe, disabling lumbago, which occured following sudden onset throat soreness, showed a stronger response against SEB (SI; 73.7 39.7), as compared with that of PA patients without such an episode (SI; 42.6 18.1). However this difference did not reach significance. Several immune abnormalities, including positive antinuclear antibodies or rheumatoid factor were observed mainly in the group experiencing such an episode of severe lumbago. Reverse transcriptase-polymerase chain reaction (RT-PCR) demonstrated that predominant expression of the T cell receptor (TCR) Vbeta 17 was commonly detected in both synovial tissues and paired peripheral bloods in two cases examined. In one case, Vbeta 12 was preferentially expressed, and in another case, Vbeta 10, 15 and 19 were also strongly expressed in the infiltrating lymphocytes in the synovial tissues. Our data raised the possibility that staphylococcal superantigens may also play an exacerbating role in PA.
Eur J Dermatol
PMID:Peripheral blood mononuclear cell proliferative response against staphylococcal superantigens in patients with psoriasis arthropathy. 992 Sep 80

The objectives of the present study were to characterize and compare the repertoire of cytokine-genes transcribed in skin homogenates obtained from normal dogs and dogs with atopic dermatitis (AD) using a reverse-transcriptase polymerase chain reaction and canine-specific cytokine-gene primers. Whereas IL-4 and IL-5 cytokine-gene transcripts were detected more commonly in atopic skin biopsy homogenates, IL-2 mRNA was amplified more often from normal control specimens. IFN-gamma mRNA was detected in 5/29 atopic specimens, 4 of them obtained from the only dog with chronic skin lesions. One-fourth of atopic samples exhibited clear type-2 cytokine profiles; the remainder did not demonstrate polarized repertoires. Conversely, type-1 cytokine profiles were characterized in one-fourth of normal control specimens. The present study establishes, for the first time, the transcription of type-2 cytokine-genes in the skin of dogs with AD. Future experiments investigating the cellular origin and dynamics of allergic cytokine-gene transcription are needed to confirm whether or not canine AD could be considered an immunological model for a human disease.
Exp Dermatol 1999 Jun
PMID:Toward a canine model of atopic dermatitis: amplification of cytokine-gene transcripts in the skin of atopic dogs. 1038 38

The migration of Langerhans cells is an initial event in the sensitization phase of contact sensitivity. Langerhans cells travel from the epidermis to the regional lymph node, and can be variously modulated in the skin where many cytokines are released from epidermal cells, dermal cells, T helper (Th) cells, and other inflammatory cells during the sensitization and elicitation phase of contact dermatitis, and thus induce an altered inflammatory skin reaction. The modulatory effect of the cytokines released in the skin, such as IL-1beta, GM-CSF, and TNF-alpha as epidermal cytokines, IL-2, IL-12, and IFN-gamma as Th1 type cytokines, and IL-4 and IL-10 as Th2 type cytokines, was analyzed using the chemotactic chamber method in this study. Both GM-CSF and TNF-alpha induced the migration of human Langerhans cells in vitro, whereas IL-1beta, IL-2, IL-10, IL-12, and IFN-gamma had no effect on Langerhans cell migration. In contrast, IL-4 inhibited Langerhans cell migration in a dose dependent manner. The inhibitory activity of IL-4 was reversed by both anti-human IL-4 monoclonal antibody and anti-human IL-4 receptor monoclonal antibody. IL-4 inhibited the Langerhans cell migration induced by both TNF-alpha and GM-CSF. Furthermore, anti-TNF-RII monoclonal antibody inhibited both random migration and the migration induced by TNF-alpha, but not that induced by GM-CSF. A reverse-transcriptase-polymerase chain reaction and fluorescence-activated cell sorter analysis revealed that TNF-alpha up-regulated and IL-4 downregulated the TNF receptor II (TNF-RII) expression of Langerhans cells at both the mRNA and the protein levels. The pretreatment of Langerhans cells with TNF-alpha enhanced the migration of Langerhans cells and the expression of TNF-RII. After pretreating Langerhans cells with TNF-alpha, IL-4 inhibited both the migration of Langerhans cells and the expression of TNF-RII in a time dependent manner. These results indicate that IL-4 inhibits the migratory activity of Langerhans cells by downregulating the expression of TNF-RII in human Langerhans cells and thereby modulates the immune response in the skin.
J Invest Dermatol 1999 Oct
PMID:IL-4 inhibits the migration of human Langerhans cells through the downregulation of TNF receptor II expression. 1050 38

Cells that have been irradiated with ultraviolet light (UV) suffer damage to their DNA, primarily in the form of covalent linkage between adjacent pyrimidines. Such photoproducts represent blocks to RNA and DNA polymerases and are potentially mutagenic. Blockage of RNA polymerase II by a photoproduct in the transcribed strand of an active gene leads to induction of the p53 protein, which induces pleiotropic responses that may include apoptotic cell death. If a cell survives, the blocked polymerase targets the nucleotide excision repair machinery to the site of the lesion, which is repaired in an error-free manner. Repair coupled to transcription in this manner strongly influences the mutation spectrum induced by UV, reducing the proportion of base substitutions that arise from photoproducts on the transcribed strand. If the damage persists when the DNA is replicated in S-phase, either because the cell is unable to repair the damage or because there is insufficient time between the induction of damage and the onset of S-phase. To do so, the replicative DNA polymerase complex may be blocked. In this situation, lesion bypass can be accomplished using an error-free mechanism, or using an error-prone mechanism that involves the newly described, non-processive DNA polymerase zeta encoded by the human homolog of the yeast REV3 gene.
J Investig Dermatol Symp Proc 1999 Sep
PMID:DNA repair, DNA replication, and UV mutagenesis. 1053 99


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